The present invention relates to a locking device for a vehicle seat, in particular a locking device located in an adjuster of a motor vehicle seat, having at least two locking elements which can be moved relative to each other and can be brought into engagement, with the engagement being maintained by at least one securing element which is mounted for pivoting about a rotational axis.
In a known locking device of this type for locking a fitting of a vehicle seat having a backrest which can pivot freely, there is a pivotable detent pawl for locking the fitting upper part, a control cam connected in a rotationally fixed manner to the detent pawl, an intercepting element for supporting the detent pawl in the event of a crash, and a spring-loaded clamping element, which acts on the control cam, for clamping the detent pawl relative to the fitting upper part. The intercepting and clamping elements, which are for acting as securing elements, are mounted pivotably and are provided with suitable active surfaces. In practice, some things remain to be desired, for example with regard to the outlay involved in production.
One aspect of the present invention is the provision of a locking device for a vehicle seat, in particular a locking device located in an adjuster of a motor vehicle seat, having at least two locking elements which can be moved relative to each other and can be brought into engagement where they are secured by at least one securing element that is mounted, in a balanced manner, for pivoting.
By virtue of the securing element being mounted in a balanced manner, i.e. the rotational axis of the securing element runs through its center of gravity, mass forces of inertia do not, in the event of a crash, produce a resulting torque which would cause a moment of momentum, i.e. a pivoting movement, of the securing element. As a result, an acceleration of the securing element, which could have an opening effect on further securing elements via connecting means, is avoided, with the result that the securing element behaves in a manner which is neutral in terms of acceleration. In the case of the known locking devices having securing elements which are mounted outside the center of gravity, the above-mentioned problems may occur, particularly if the securing elements are connected together, and the problems have to be prevented by appropriate, dimensionally accurate machining of the components.
At least one section of material is preferably integrally formed on the securing element as a balancing weight. This integral design is neutral in terms of outlay in the case of production. In order to avoid stresses and fractures if overloaded, the section of material may be of lug-like design with rounded or continuous transitions. For a simpler balancing of masses, two sections of material are preferably provided at the same distance from the rotational axis, specifically, as a rule, with respect to the rotational axis, on the side facing away from the active surface of the securing element. A flat design of the securing element not only saves structural space, but also simplifies the balancing. Preferably taken into consideration as the balanced securing element are clamping and/or intercepting elements which are suitable for clamping and, in the event of a crash, for supporting locking elements designed as pivotable detent pawls.
The locking device according to the invention can be used for various adjusters, i.e. both for rotational adjusters, such as, for example, fittings of vehicle seats having a backrest which can be varied in inclination and/or can pivot freely, and also for linear adjusters, such as, for example, longitudinal adjusters or vertical adjusters in combination with diagonal struts. The locking device according to the invention can also be used for the locking of various positions of a foldable vehicle seat.